Method of riveting



Feb. 2, 1946. P. B. KELLER ETAL.

METHOD'QF RIVETING Filed De'. 3l, 1943 Patented ret. ze; i946 fr y, 2,395,661

, UNITED STATES PATENT .OFFICE i METHOD 0F RIVETING Philip B. Keller, Santa Monica, and Donald Jel- Y inek, Losl Angeles,` Calif., assignors to North American Aviation, Inc., Inglewood, Calif., a

i This invention relates to the art of setting se curing devices of the composite rivet type, Wherein a shear-resistant, hardened pin has an integral head at one end and at its other end a head formed by a malleable collar embracing and forced into an annular groove in said other end. Qne of the objects of the invention is to provide an improved l method of forming such a securing device head. Anotherobject is to provide an improved tool for forming the head on a securing device of this type. A

In the drawing, like reference characters designate similar parts in the several views.

Fig. 1 is a sectional view illustrating the beginning of a rivet setting operation in accordance with the invention.

Fig. 2 is an enlarged sectional viewshowing the completion vof the rivet setting operation and illustrating the tool in which the invention is i( embodied.

'I'he present invention constitutes an improvement upon the art of riveting set forth in United States Letters Patent No. 2,355,579, granted Aug. 8. 1944, for method of riveting. The method disclosed in that application embodies the insertion of a hardened steel rivet pin I through aligned openings Ii and I2 in a pair of members I3 and Il to be secured together, the rivet pin having at one end a head I5 adapted to engage one of the members I3, Il, and having at its other end a portion I 8 designed to project beyond the parts that are being secured together and having an annular groove I I into which a. collar I8 of aluminum or other malleable metal is forced by means of a tool I9. The groove I'I is defined generally by conical surfaces and 2I connected by a curved surface. The angle ofthe surface 2| with reference to the `longitudinal axis of the pin I8 is considerably greater than that of. the surface 2D. It is suiiiciently obtuse so thatthe corporation of Delaware .l A Application December 3l, 194.3, .Serial No. 516,366 y i 1ciaim..tc1.'zs4s) 'angle of the surface 20.

Any excess metal sheared from the end ofthe collar I8 against the shearing edge 24 of the -pin I0 is discharged from the tool through an opening 25. y

In the past it has been customary to use a tool wherein the angle of the conical mouth 22 is the same as the angle of the surface 20, in order that the wall thickness of the collar I8 might be uniform in the formed head.

' Our invention provides an arrangement wherein the conical mouth 22 of the tool I9 makes an angle that is substantially more acute with reference to the axis of the tool and pin than is the Thus the surfaces 20 and 22 are arranged in outwardly dverging relation subtending between them an angle a. For

the purpose of the present invention, we nd that good results are secured where the angle a is in the neighborhood of 5 degrees.

The mouth 22 at its outer extremity forms a relatively sharp corner with the end of the tool, in contrast to the rounded corner employed on the prior tool. The sharp corner has two functions. It confines the collar, where the tool nears the end of its stroke, so that the pressure against the collar may result in some flow of the metal of the collar in the direction opposite to that of tool movement as indicated by the arrow 21 in Fig. 2, thus setting the outer end of the collar ilrmly against the lshoulder 2|. Secondly, it presses the base of the collar rmly around the base of the conical surface 20 as indicated by the y arrow 28. s

More particularly, the annular groove I1 is made up -of a n'usto-conical base connected by a y curved surface to a reversely-disposed irustocollar I8 will make adequate abutting contact therewith for transmitting tension loads from the pin to the member Il. It has been found quite satisfactory to arrange the surface 2| at an angle oi60 degrees with reference to the axis of the,

ward the member I4. A bucking bar 23 is used to engage the head oi' the rivet to support the pin It under the pressure oi' the setting tool I9.

' conical top portion, and the tool includes a frustoconical shaped interior surface. lThe anglarlty the rivet pin is more acute-than the angle of the vsurface of the truste-conical base of the annular groove' with respect to such longitudinal axis of therivet. Thus, movement of the tool oven-the collar results in a flow of the material of the collar inwardly into tightgiltting engagement with the" frustoconical base and the curved surface of the annular groove and upwardly into tight fitting engagement with the surface of the reversely disposed frusto-conical top portion thereof as indiwould gap away from the surface 20 at thebase thereof as indicated by the numeral 28. The

- present invention eliminates both of these faults of theprevious practice.- The flow of metal toward the shoulder 2| is facilitated by the diverging angle betweenthe tool'surface 22 and the pin surface 2|) in the direction ofthe shoulder 2|.

The forces set up in the collar |8 as indicated by the arrows 21 and 28 result in the collar being Y placed under compression between the shoulder 2| and the member 4 and the pin I0 consequently being placed under` tension to draw the members |3 and Il tightly together. The result is a very tight joint.

The foregoing may be taken as illustrative of one form in which the invention may be embodied, it being our intention to cover in our claim the use of any equivalent arrangement or apparatus.

We claim as our invention:

The method of setting a. malleable collar into.

an annular groove in a rivet pin,`and which anasomo? nular groove is made'up of a frusto-conical base connected by a curved surface to a reversely disposed frusto-conical top portion, which consists in applying deforming pressure to the exterior of the collar by a tool having a frusto-conical in. terior surface, the angularity of which surface with respect to the longitudinal axis of the rivet pin is more acute than the angle of the surface of the frusta-conical base of the annular groove in the rivet pin with respectto the longitudinal axis of the rivet pin whereby movement of the tool over the collar results in flow of the material of the collar inwardly into tight iitting engagement with the truste-conical base and the curved connecting surface of the annular groove and upwardly intotight fitting engagement with the surface of the reversely disposed frusto-conical top portion of said rivet pin groove.

PHILIP B. KELLER.

DONALD JELINEK. 

